Conventionally, as a sensor used to detect an angular velocity, a gyro sensor as shown in, e.g., Patent Literature 1 has been known. The gyro sensor of this type has a drive weight which is vibrated in an in-plane direction of a substrate, and detection weights each connected to the drive weight via a detection spring. The gyro sensor performs angular velocity detection on the basis of such a mechanism that, while the drive weight is driven/vibrated, the detection weights are vibrated in a direction perpendicular to the substrate by the application of an angular velocity. The gyro sensor shown in Patent Literature 1 has a structure in which the drive weight and the detection weights are arranged in the form of a disk. During the detection of the angular velocity, the drive weight is vibrated so as to cause oscillation around the center of the disk, thus allowing angular velocity detection to be performed. That is, on the basis of the application of the angular velocity, the detection weights facing each other on both left and right sides of the disk center are vertically vibrated in a seesaw manner in a direction (z-axis direction) perpendicular to a disk plane. Accordingly, by obtaining a differential output based on the vertical vibration on the left and right sides, angular velocity detection is performed.